User's Manual

LPP0108IG001 54 Version - Preliminary – 06/20/08
7.13. Set BCI parameters for an ActiveKey2 - Appendix 3
Example 1: Set BCI parameters for an ActiveKey2, 230mAh Li-Ion battery, and 5V regulated wall charger.
Step 1 - Given:
Variable Value Description
I
SYS
V
MAX
50mA
6.050 V
AKII idle current
AKII max. voltage on charger input
C
1
R
ID
Temp_max
Temp_min
230mAh
4.7kohm
+60C
-20C
Battery1 capacity (Nitro battery), ID,
and temp. specs.
C
2
- Battery2 capacity
C
3
- Battery3 capacity
C
4
- Battery4 capacity
C
5
- Battery5 capacity
Vchg1 5.00V
Vchg1_Max = 5.725V
Vchg1_Min = 4.725V
Charger1 (USB charger)
Vchg2 5.00V
Vchg2_Max = 5.05V
Vchg2_Min = 4.95V
Charger2 (Regulated wall supply)
Charger3 - Charger3
Charger4 - Charger4
Charger5 - Charger5
Step 2 - Calculate system parameters:
Variable Value Description
CI CI = 1 x C
1
= 230mA Constant current (800mA max.)
Iprechg C
1
/10 = 23mA Precharge current (Locosto on)
I
EOC
C
1
/20 = 12mA EOC current
T
CI_CHG
(<#_ci_elements> / 10) x
(C
1
/ CI ) x 60 =
0.7 x 60 = 42min
CI charge time (min)
T
CV_CHG
(1-<#_ci_elements> / 10)
x C
1
x 60 / (0.5 x (CI -
I
EOC
) + I
SYS
)
= 0.3 x 230 x 60/ (0.5 x
(230 -12) + 50)
= 26 min
CV charge time (min)